O.k. guys, I have a question. I have posted this question several times with teh folks at Procharger, but all they keep doing is mailing me sales flyers and not answering my question.

I am building a Tri-power 383 for my '69. I have seen Procharger setups for dual quad engines but never anything for Tri-power setups.....why not?? Is there some obvious reason why one of these setups could not be made to adapt to a Tri-power setup? I know that there are benefits of going to dual carbs or other applications, but if a person is absolutely stuck on the idea of using Tri-power, do you guys think it could be done and if so, do you think it would be beneficial. I've already considered using Nitrous and may go that way, but I'm tinkering with the idea of supercharging. I would think one problem would be to develop a bonnet system that would divide the air equally. If it could be done, I bet it could be made to be pretty cool looking. I like looks in a car as much as go power.

What do you guys think??

 

No ideas or opinions on this?

 

I certainly have never seen it done before, most likely due to the complexity. One thing that you would have to work through would be getting the blow through internals put together on the tri-power specific carbs, which may or may not be easily done.

It would certainly be unique, but you would basically have to figure out a lot of things on your own as you go. Tri-power setups were fairly rare as a performance induction system in any case, so modification thereof is going to be even more rare.

 

Glenn “Mr. Blue” at one time had a corvette tri-power air cleaner on top of his blown motor in “love is blue”, I am guessing he had three two barrels under it but I don’t know for sure. He can be found on VM, I think pewter99 banned him from here.

 

No reason why it couldn't be done. The carbs would have to handle being pressurized and the blower sized to the carbs. I'm not sure that the 3-carb setup would allow optimum airflow for that supercharged application, but it would be to look at. The only difficulty would be designing and fabricating a plenum that would fit over the carbs...something in stainless steel, perhaps.

 

Normally tri-powers have the center carb for idling/cruising and the outer carbs for acceleration....not sure how that would work with a blow through set up.

Nick

 

Anything is possible but the engineering and one off parts would probably make it cost prohibitive. The supercharged 2x4 setups use both carbs throughout the RPM range kicking in the secondaries when needed so you can cram air through both carbs. In a tripower setup the secondaries are the two end carbs. A lot more difficult. Nitrous is easier and doable. Here is a photo off my tripower with a 150 HP plate system.

 

You are going to set up the outer two carbs the same [no matter what you do], so it boils down to two new setups for the three carbs. I think that's about the same number as for the two 4-barrels. You just need to get the idle and low speed mixture, cruise and WOT to have good air/fuel mixtures. Do your research and make initial rough settings, then take it to a dyno...or put a wide-band O2 sensor/readout on it and 'tinker' away.

 

Thanks guys. I appreciate the input. I will tinker a good bit with it, but I was a little disappointed that I could never squeeze out any info from the Procharger guys despite all my tries.

I've lent thought to the same conventions...that a dual quad setup pretty much operates both carbs in sequence and a Tri setup runs off the center carb until WOT. I've starting sketching some ideas of maybe fabbing some kind of stainless plenum to cover the 3 carbs and had thought of using a series of butterfly doors to open passage ways to the end carbs for the supercharged air to run through. Those would tie in with the carb linkage so they would engage at WOT. Until WOT, the center carb would get its air supply through the supercharger and the end carbs through conventional small air cleaners on side ports.

Not sure if that is possible, but makes some sense to me. Anyway you look at it, it's going to make for a lot of fabbing, a lot of synchronizing of several moving parts and a good bit of head scratching. I'm also equally sure that it will involve my coining of a few new cuss words too.

I've certainly not ruled out Nitrous either, but like you guys said, the supercharging would be pretty different. I've always enjoyed working on things off teh norm, just to see if I could do them. If I do go the Nitrous route with no Supercharging....or even if I just go with my plain tri-power with no add-ons, I've in the process of designing / building some coooooooool air cleaners to set on top. I think you guys will get a kick out of them. I've already been tinkering with them. I'll try to post pics when things get a little more along. I'm notorious for buying pieces and parts for my idea and setting it aside for a while until I get an itch to hit it again.

Thanks again.

 

Try the other Supercharger dealers.............

 

I think you're making this way too hard. The outer carbs already have butterfly valves in them...and they don't open up until you hit 50% throttle anyway (I would hope you'd go to a mechanical linkage--not the cobbled-up vacuum apply system that Chevy designed). In other words, you're going to set up the center carb for idle, takeoff and cruise capabilities....and all three for when you go WOT. What else does it need to do? You can probably do 100+ mph on 50% throttle--the end units won't even be breathing till then.

 

I am using mechanical linkage. I guess my train of thought was that I would need to prevent the supercharged airflow from flowing to the end carbs until they were engaged at WOT, but as soon as I read your post, I realized exactly what you were saying. Those carbs aren't really doing anything until the linkage is engaged. I've had it in my head that some sort of plenum needed designed to feed equal amounts of air to each carb when all 3 are engaging. I'm not sure that one large bonnet covering all 3 wouldn't do. When idling or cruising at something less than WOT, the center carb would be drawing it's air solely through the charger. I don't know enough yet about these setups to see all the details of it I guess.

Thanks.

 

I think you're on the "right track" now. The supercharger doesn't really change anything on the operation of the carbs...except the air pressure and the amount of fuel required to mix with the pressurized air; the carbs work exactly the same way with high(er) pressured air. One plenum with 3 openings [in the correct location] will get the job done. Just include any height differences in the tops of the 3 carbs.

 

Centrifugal blowers work better with single plane manifolds and tri power manifolds are dual plane. You would make more power with a good single plane manifold.

Plus fitting a centrifugal blower in a C3 is tricky.